Every student enrolled in a Catholic School in the State of Texas shall be immunized against vaccine-preventable diseases caused by infectious agents in accordance with the immunization schedule adopted by the Texas Department of State Health Services. A student who fails to present the required evidence shall not be accepted for enrollment. The only exception to the previous requirement is a medical exemption signed by a licensed physician (M.D. or D.O.) authorized to practice in the State of Texas, including the physicians' license number. 

Immunizations are not in conflict with the Catholic faith. Conscientious objections or waivers, which may be permissible for attendance in public schools, do not qualify as an exemption in Catholic Schools in Texas. (Atty. Gen. Op. GA-0420)

This policy was adopted by the Texas Catholic Conference of Bishops Education Department in December 2008 and voted on April 3, 2017, to keep it as written with no changes by the Bishops of Texas.

Texas Administrative Code, Rule 97.62
The statement must state that, in the physician's opinion, the vaccine required is medically contraindicated or poses a significant risk to the health and well-being of the child or student or any member of the child's or student's household. Unless it is written in the statement that a lifelong condition exists, the exemption statement is valid for only one year from the date signed by the physician.